Simple Machines
A simple machine that cuts. Example a knife or an ax.
Wedge
A boy pushes a box with a force of 50 N across the floor for a distance of 4 meters.
How much work does he do on the box?
200 J
A lever allows you to lift a 60 N load using only 20 N of effort.
What is the mechanical advantage?
3
The force exerted by the person on the machine.
Input Force
What type of machine is a seesaw?
lever
A girl lifts a 10 kg backpack to a shelf 2 meters high in 4 seconds.
How much power does she use?
49 Watts
A pulley system lets you raise a 100 N weight with 25 N of effort.
What is its mechanical advantage?
4
The force exerted by the machine on the object.
Output Force
A simple machine that has a wheel with a groove for a rope. Example of this is the flagpole.
pulley
If 600 J of work is done in moving an object 3 meters, how much force is applied?
200 Newtons
A crowbar is used to lift a rock that weighs 300 N. If the user applies 75 N of force, what is the mechanical advantage of the crowbar?
4
It is the stored energy an object has because of its position or condition.
Potential Energy
What type of simple machine is a wheelbarrow?
wheel and axle
A motor does 1200 J of work in lifting a load with a power of 400 W.
How much time does it take?
3 seconds
A pulley system has a mechanical advantage of 4. If the input force is 30 N, what is the output force?
120N
What is the formula in solving for the kinetic energy?
1/2 mv2
What two simple machines make up a pair of scissors
lever and wedge
A hiker lifts her 12 kg backpack from the ground to the top of a 10-meter-high hill. Then, she places it on a rock 1.5 meters above the ground while resting halfway. What is the potential energy of the backpack at the halfway point (1.5 m)?
176.4 J
If a lever has an MA of 3, how much effort is needed to lift a 90 N load?
30N
force, distance and direction